Fabrication Defect

4 cases · 53 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Standard: AISI clear all

Fabrication Defect — sub-branches

Coating Defect 1Heat Treatment Defect 2

Results

SortNewestOldestTitle A-ZTitle Z-A
Aspect of the external surface of the broken cylindrical roller bearing presenting a polished external diameter and a the rupture with brittle characteristics (flat and parts that were lost).
726
VIEW
ML00131 / Apr.2018
Brittle Failure of a Soft Roller Bearing
M - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Cm - Aspect Before AnalysisDf - Fracture
Longitudinal cracks in the surface of the pin, detected by dye check, after high pressure hydrostatic test.
658
VIEW
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - Aspect by NDTDf - General View
Shaft pinion presenting the bearing surface, with machining markes, from where the thermal spray layer was detached. The diameter of the 880 mm long shaft in this region is about 75 mm.
426
VIEW
ML00108 / Dec.2017
Thermal Spray Layer in a Pinion Shaft
M - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Cm - Aspect Before AnalysisDf - General View
Micrographic detail of the forging lap defect that appears at the nut surface like a crack, filled with oxides. The nut presented a martensitic structure in the center of the nut, but in the regions adjacent to the defect the structure is ferritic-bainitic due to decarburization. There are several globular oxides (grey spots) that became entrapped during the forging.
654
VIEW
ML00099 / Jan.2018
Forging Defect in a Cadmium Plated Nut
M - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Cm - Nital Etched Micrography by OMDf - Crack

More from these cases

ML00131 — Brittle Failure of a Soft Roller BearingM - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Macrography of a circumferential section of the roller bearing, showing two different structures: one, white and hard (64 HRc), close to the external surface; and the other, dark and soft (21 HRc), close to the internal surface. The hardness in the thickness, close to the interface, is about 50 HRc.
122
VIEW
ML00131 / Apr.2018
Brittle Failure of a Soft Roller Bearing
M - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Cm - NItal Etched MacroDf - Duplex structure
Aspect of the broken cylindrical roller bearing, presenting the internal diameter full of cracks; and the fracture revealing two different morphologies, flat and smooth close to the external diameter (that appeared white in the macrography); and rough close to the internal diameter (that appeared dark in the macrography).
107
VIEW
ML00131 / Apr.2018
Brittle Failure of a Soft Roller Bearing
M - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Cm - Aspect Before AnalysisDf - Fracture
Aspect of the internal diameter surface presenting several cracks in the axial direction, caused by the contact with the shaft. The roller bearing presented a too low hardness level (21 HRc average) in this ID position.
90
VIEW
ML00131 / Apr.2018
Brittle Failure of a Soft Roller Bearing
M - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Cm - Aspect Before AnalysisDf - Internal Surface
Detailed aspect of the cracks in the internal diameter surface, where the hardness level was too low. These are typical overloading cracks.
76
VIEW
ML00131 / Apr.2018
Brittle Failure of a Soft Roller Bearing
M - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Cm - Surface AspectDf - Cracks
Micrography of an axial section of the roller bearing, at the external surface, where the hardness level was about 64 HRc (higher than the limit of 58HRc to 62 HRc).
86
VIEW
ML00131 / Apr.2018
Brittle Failure of a Soft Roller Bearing
M - Wear Resistant SteelP - Roller BearingAp - Mechanical IndustryCd - Heat Treatment Defect
Cm - Nital Etched Micrography by OMDf - Close to the External Surface

+14 more from this case →

ML00110 — Non Conformance in Spray and Fuse PinM - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Micrography, as polished, of the transverse section of the forged pin with the layer applied by a (thermal) spray and fuse process. The layer presented entrapped pores and globular oxides. It was melted after application by thermal spray (in this case using a flame) but the pin was not heat treated after the full application and melting of the layer and the base metal is ferritc-pearlitic.
51
VIEW
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Transverse Section
Micrography, as polished, of the transverse section of the forged pin with the layer applied by a (thermal) spray and fuse process. The layer was melted after thermal spray application and the layer presents a continuous matrix, but there are globular oxides and pores entrapped.
36
VIEW
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Surface Layer
Micrographic detail, as polished, of the transverse section of the forged pin at the interface between the pin and the spray and fuse layer. The interface presents globular oxides and small pores, entrapped.
35
VIEW
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Surface Layer
Low magnification micrography of the interface between the pin and the spray and fuse layer. Close to the surface, under the layer, the pin presents a ferritic perlitic structure, non conform with the high strenght requirement. Transverse section.
37
VIEW
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - As polished micrographyDf - Low Mag
Micrography of the pin close to the interface with the spray and fuse layer. Transverse section. The fuse was conducted in high temperature and the pin was cooled very slowly, forming a ferritic-perlitic structure even for this high hardenability base metal.
35
VIEW
ML00110 / Jan.2018
Non Conformance in Spray and Fuse Pin
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Heat Treatment Defect
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite

+6 more from this case →

ML00108 — Thermal Spray Layer in a Pinion ShaftM - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Detail of the detached layer, about 1.5 mm thick.
48
VIEW
ML00108 / Dec.2017
Thermal Spray Layer in a Pinion Shaft
M - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Cm - Aspect Before AnalysisDf - Layer Detachment
Macrographic detail of the thermal spray layer in a position of the shaft where it was not detached. Longitudinal section of the shaft. The waves are the machining marks created to anchor the thermal spray layer, that is about 1.5mm thick.
41
VIEW
ML00108 / Dec.2017
Thermal Spray Layer in a Pinion Shaft
M - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Cm - NItal Etched MacroDf - Longitudinal Section
Micrography of the thermal spray (TS) layer showing the different alloys, gray oxides and black voids. The Ni base TS alloy is of a yellow colour at the interface with the shaft substrate (in the left). The Cr base TS alloy appears white, similar to the shaft substrate. Longitudinal section of the shaft.
42
VIEW
ML00108 / Dec.2017
Thermal Spray Layer in a Pinion Shaft
M - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Cm - As polished micrographyDf - Coating Layer
Micrographic detail, as polished in a longitudinal section, of the interface between the shaft substrate and the thermal spray layer. In the left it is the shaft substrate also presenting parts of aligned inclusions (gray). In the center it is the Ni base TS alloy and in the right it is the Cr base TS alloy. There are also black voids and grey oxides.
33
VIEW
ML00108 / Dec.2017
Thermal Spray Layer in a Pinion Shaft
M - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Cm - As polished micrographyDf - Coating Layer
Micrography of the interface between the shaft surface and the thermal spray layer. The shaft steel presents a quenched and tempered structure. Longitudinal section.
32
VIEW
ML00108 / Dec.2017
Thermal Spray Layer in a Pinion Shaft
M - High Strength Low AlloyP - ShaftAp - EngineCd - Coating Defect
Cm - Nital Etched Micrography by OMDf - Coating Layer

+7 more from this case →

ML00099 — Forging Defect in a Cadmium Plated NutM - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Micrography of the nut in a section transverse to the surface indication. There are several microcracks (parallel and perpendicular to the nut surface) filled with oxides. The nut presented a martensitic microstructure in the center of the thickness and a ferritic-bainitic microstructure at surface and adjacent to the defect, due to decarburization occurred during high temperature forging.
130
VIEW
ML00099 / Jan.2018
Forging Defect in a Cadmium Plated Nut
M - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Cm - Nital Etched Micrography by OMDf - Crack
The general aspect of the 1 1/8" 2H nut, presenting rejectable indications that appear like cracks, located in the face and in the lateral side of the nut.
46
VIEW
ML00099 / Jan.2018
Forging Defect in a Cadmium Plated Nut
M - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Cm - Aspect Before AnalysisDf - General View
Aspect in detail of the 1 1/8" 2H nut face, presenting rejectable indications that appear like cracks.
49
VIEW
ML00099 / Jan.2018
Forging Defect in a Cadmium Plated Nut
M - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Cm - Aspect Before AnalysisDf - Lap
The general aspect of the lateral side of the 1 1/8" 2H nut, presenting a rejectable indication that looks like a straight crack.
48
VIEW
ML00099 / Jan.2018
Forging Defect in a Cadmium Plated Nut
M - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Cm - Aspect Before AnalysisDf - Lap
Micrographic detail of the lap at the nut surface, as polished. The 20 microns cadmium layer is evident, penetrating in the lap.
46
VIEW
ML00099 / Jan.2018
Forging Defect in a Cadmium Plated Nut
M - Medium Carbon SteelP - NutAp - PipingCd - Fabrication Defect
Cm - As polished micrographyDf - Lap

+2 more from this case →